alc203-lf Realtek Semiconductor Corporation, alc203-lf Datasheet - Page 13

• Manufacturer Part Number: alc203-lf
• Description: Two-channel Ac?97 2.3 Audio Codec
• Manufacturer: Realtek Semiconductor Corporation

6.1.4 MX06 MONO_OUT Volume
Default: 8000h
Register 06h controls the mono volume output. Mono output is the same data sent on all output channels. Each step in bits 4:0
corresponds to a 1.5dB increase/decrease in volume, allowing 32 levels of volume from 00000 to 11111.
6.1.5 MX0A PC BEEP Volume
Default: 8000h
This register controls the input volume for the PC beep signal. Each step in bits 4:1 corresponds to a 3dB increase/decrease in
volume. 16 levels of volume are available, from 0000 to 1111.
The purpose of this register is to allow the PC Beep signals to pass through the ALC203, eliminating the need for an external system
speaker/buzzer. The PC BEEP pin is directly routed (internally hardwired) to the LINE-OUTL & R pins. If the PC speaker/buzzer is
eliminated, it is recommended to connect the external speakers at all times so the POST codes can be heard during reset.
6.1.6 MX0C PHONE Volume
Default: 8008h
Register 0Ch controls the telephone input volume for software modem applications. Because software modem applications may
not have a speaker, the CODEC can offer a speaker-out service. Each step in bits 4:0 corresponds to a 1.5dB increase/decrease in
volume, allowing 32 levels of volume, from 00000 to 11111.
Two-Channel AC’97 2.3 Audio Codec
14:13
14:5
12:5
14:5
Bit
4:0
Bit
4:1
Bit
4:0
15
15
15
0
For MMV:
For PBV:
For PV:
Type
Type
Type
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Mute Control 0: Normal
Reserved
Mono Master Volume (MMV[4:0]) in 1.5 dB steps
Mute Control 0: Normal
Reserved
Internal PCBEEP Frequency, F[7:0]
The internal PCBEEP frequency is the result of dividing the 48KHz clock by 4 times the number specified
in F[7:0].
The lowest tone is 48KHz/(255*4)=47Hz.
The highest tone is 48KHz/(1*4)=12KHz.
A value of 00h in F[7:0] disables internal PCBEEP generator and allows external PCBEEP input.
PC Beep Volume (PBV[3:0]) in 3 dB steps
Reserved
Mute Control 0: Normal
Reserved
Phone Volume (PV[4:0]) in 1.5 dB steps
1Fh
0Fh
08h
1Fh
00h
00h
00h
0 dB attenuation
46.5 dB attenuation
0 dB attenuation
45 dB attenuation
+12 dB Gain
0dB gain
-34.5dB Gain
1: Mute (-∞ dB)
1: Mute (-∞ dB)
1: Mute (-∞ dB)
9
Function
Function
Function
ALC203 DataSheet
Rev1.6